At least some content in this article is derived from information featured in Harry Potter: Wizards Unite. As such, spoilers will be present within the article.
For gameplay-specific information, please see the relevant article on the Harry Potter: Wizards Unite Wiki!
A Foe-Glass is a type of Dark Detector. It looks like a mirror, but instead of a reflection it shows the enemies of its possessor. The figures appear as "shadows" but become clearer and more visible as the enemies get closer to the possessor.
Barty Crouch Jr, while impersonating Alastor Moody, had Moody's Foe-Glass in his office during Harry Potter's fourth year at Hogwarts School of Witchcraft and Wizardry. He said he's not really "in trouble" until he can see "the whites of their eyes." Later in the school year, after Cedric Diggory's tragic death, it was revealed that Crouch's enemies shown in the glass were Albus Dumbledore, Minerva McGonagall, and Severus Snape, all notable members of the Order of the Phoenix. Crouch, however, was too focused on Harry at the time that he did not notice the shadows within the glass were becoming clearer, warning him that the three were soon approaching, which ultimately led to his exposure and downfall.
When Harry and the other members of Dumbledore's Army first entered the Room of Requirement, he found, among other Dark Detectors, the fake Moody's Foe-Glass. By this time it was cracked, but still functional.
- Harry Potter and the Goblet of Fire (First appearance)
- Harry Potter and the Goblet of Fire (film)
- Harry Potter and the Order of the Phoenix
- Harry Potter: Wizards Unite